Question

1) What makes x-ray crystallography more difficult than cryo EM in many cases?

a.crystalizing proteins can be very hard

b.The x-ray process requires a great deal of energy

c.crystallography requires very high tech computers

d.x-ray crystallography can only be used for very small proteins

2)After breaking up your cells with a mortar and pestle, you then centrifuge your sample at a low speed. Where would you expect to find your protein if it is normally located in the cytosol?

a.pellet

b.inside the ER

c.supernatant

d.inside nuclei

x-ray crystallography can only be used for very small proteins

Answer 1

1. X ray crystallography becomes challenging in many cases when compared to cryo em in many cases because A the molecule of interest have to be crystallised. Some proteins or important macromolecules simply can not be crystallised; others have their structures irreversibly changed by crystallisation. So Cryo em needs to be used for such cases.

Hence option A is the correct one.

2. The proteins remains in the supernatant after the low rpm centrifugation.